respiratory pharmacology Flashcards
what are the different bronchodilators?
- adrenergic agonists: beta 2 agonists
- muscarinic antagonists/anticholingergics
- ipratropium-short acting anti muscarinic
- methylxanthines
give 3 examples of adrenergic agonists
- salbutamol
- salmeterol
- formotetol
what is tiotropium?
long acting anti muscarinic
give an example of a methylxanthine
aminophylline
what are the 2 types of anti inflammatory drugs used for the airway?
- steroids
- leukotriene receptor antagonists
give an example of one oral and one inhaled steroid
oral = prednisolone inhaled = beclomethasone
how do pressurised metered dose inhalers (pMDIs) work?
- deep inhale
- inhale and puff
- hold breath for slow 10 count
- exhale slowly
- wait one minute before second puff
- use spacer/aerochamber
how do dry power inhalers work?
one inhalation not a puff
what is the duration of salbutamol?
short acting (begin immediately, 3-5 hour duration)
what are the routes for salbutamol?
inhaled or nebuliser (higher dose), intravenous (very rarely used)
what is the mechanism of action of salbutamol?
binding to beta 2 receptors in the lungs results in relaxation of bronchial smooth muscle. it is believed that salbutamol increases cAMP production by activating adenylate cyclase and the actions of salbutamol or mediated by cAMP. it is a short acting beta agonist
when is salbutamol used?
asthma and COPD
what is the duration of salmeterol?
long acting (begin 2-30 mins, 10-12 hour duration)
what are the routes for salmeterol?
inhaled
what is the mechanism of action for salmeterol?
long acting beta-adrenoreceptor agonists
when is salmeterol used?
- asthma in patients requiring long term regular bronchodilator therapy on ICS not PRN and always used with ICS in asthma
- COPD for persistent symptoms despite SABA (either LABA/LAMA combinations of ICS/LABA combination)
what is the duration of formoterol?
long acting (with short onset similar to salbutamol but with prolonged duration 10-12 hours)
what are the routes for formoterol?
inhaled
what is the mechanism of action for formoterol?
long acting beta-adrenoreceptor agonist
when is formoterol used?
asthma and COPD, combined with ICS (always) for asthma
what is the duration of tiotropium?
long acting (24 hours), once daily
what is the route of tiotropium?
inhaled (dry power hand inhaled/mist respimat)
what is the mechanism of action of tiotropium?
long acting muscarinic antagonist (LAMA). it had similar affinity to the subtypes of muscarinic receptors M1 to M5. in the airways, it exhibits pharmacological effects through inhibition of M3 receptors at the smooth muscle leading to bronchodilator
what are the indications to use tiotropium?
- stable COPD: symptoms despite SABA (any severity and with LABA)
- asthma: in not improving ICS/LABA specialist advice from hospital
what are the key features of ipratropium?
- short acting antimuscarinic agent
- onset 30 minutes, lasts for 6 hours
- nebulised
- nebulised for acute presentations of COPD and sometimes asthma
what is the duration of theophylline?
half life around 5 hours in a healthy adult
what are the routes of theophylline?
oral/intravenous
what is the mechanism of action for theophylline?
phosphodiesterase inhibitor that requires monitoring of level (blood level)
what are the indications to use theophylline?
- oral: COPD and asthma with persistent symptoms
- intravenous: COPD and asthma in medical emergencies
what are the adverse effects of bronchodilators?
- tachycardia
- nervousness, irritability, tremor
- inhaled preparations: less common
- oral preparation (hardly used) and intravenous: more side effects are common - tachycardias/angina
- usually dose related
what are the characteristics of systemic glucocorticoids?
- IV or oral
- stronger effects as higher doses
- action unaffected by inspiratory effort/inhaler technique
- more side effects, especially with long term therapy
give an example of a systemic glucocorticoid
prednisolone
what are the characteristics of inhaled glucocorticoids?
- localised action
- fewer side effect: some absorption occurs
- disease may prevent penetration of drug to affected areas
give 3 examples of inhaled glucocorticoids
- beclometasone
- fluticasone
- budesonide
what are the airways effects of glucocorticoids?
- decrease release of inflammatory mediator
- decrease infiltration and action of white blood cells
- decrease airways oedema
- decreased airways mucus production
- increase number and sensitivity of beta-2 receptors
what are the adverse effects of inhaled glucocorticoids?
- oral candidiasis: white plaques in mouth
- dysphonis
what are the general adverse effects of glucocorticoids?
- adrenal suppression
- bone loss: exercise, vit D, calcium
- slow growth in children, but ultimate height
- increased risk of cataracts and glaucoma
- increased risk of infection
- gastric ulceration
- hypertension
- diabetes
- mood distrubance
what are the 3 combination of drugs used in ICS/LABA combination inhalers?
- formoterol/budesonide
- formoterol/beclomethasone
- salmeterol/fluticasone
what is an example of a combination of drugs used in LAMA/LABA combination inhalers?
tiotropium/olodaterol
what are the 3 drugs used in an ICS/LABA/LAMA combination inhaler?
beclomethasone/formoterol/glycopyrronium
what are the different drugs used for allergic rhinitis?
- antihistamines: H1 antagonists, side effects = drowsiness, dry mouth, dry eyes, confusion
- intranasal glucocorticoids
- montelukast: inhibit leukotriene receptors, decrease inflammation, bronchoconstriction, oedema, mucus, recruitment of eosinophils
- sympathomimetics
what are the different types of respiratory infections?
- bronchitis: COPD and asthma
- community acquired pneumonia (CAP): severity scoring
- hospital acquired pneumonia HAP (early and late)
- ventilator acquired pneumonia (VAP)
- aspiration
- bronchitis doesn’t equal pneumonia: have different treatment
what are the 2 types of antibiotics used to cover respiratory infections?
- amoxicillin
- co-amoxiclav
what are the key features of amoxicillin?
- moderate spectrum, bacteriolytic, B lactam antibitoic
- routes: IV/oral
- use: CAP (typical), COPD exacerbations, bronchitis
- active against gram negative and gram positive bacteria
what are the key features of co-amoxiclav?
amoxicillin is susceptible to degradation by B lactamase producing bacteria so can be combined with clavulinic acid - a beta lactamase inhibitor
what are the key features of tetracyclines?
- inhibits protein synthesis
- broad spectrum action gram positive and gram negative
- useful for atypical infections
- oral route only
- side effects: GI upset, staining, teeth, lupus, alergy, photosensitivity
give an example of a tetracylcine
doxycycline
what are the key features of quinolones?
- mechanism of aciton: DNA fragmentation
- gram postiive and positive coverage (and Pseudomonas)
- route: IV/oral/inhaled
- side effects: GI upset, C difficule, tendinitis, liver upset, prolonged GTC and arrhythmia
what are the key characteristics of macrolides?
- commonly used in respiratory infection (including atypical pneumonia)
- mechanism of action: protein synthesis inhibitors
- route: IV/PO
- gram positive/limited gram negative cover
- side effects: GI, allergy, liver abnormality, prolonged GTC and interactions
